Reconfigurable circuits are circuit devices that may be reconfigured through programming to realize a variety of different functions, so long as the complexities of the desired functions are not too high. One example of a reconfigurable circuit is a Field Programmable Gate Array (FPGA) circuit.
FPGA circuits contain a variety of basic reconfigurable resources in quantities that may be used/reconfigured through programming to realize a variety of different functions. Since an FPGA circuit is reconfigurable, a variety of basic reconfigurable resources are often combined to provide a desired functionality. As FPGA circuit designs will often use several transistors for each transistor of the target function, the overall FPGA surface area required on a given die is among the largest devices to be made with a given integrated circuit technology. As a result, FPGA manufacturers are constantly faced with reducing the size of their circuit designs in an effort to reduce problems in production.
As previously indicated, modern FPGA circuit designs may use several different reconfigurable resources, such as logic gates, wires, memories, arithmetic operators, pads, and even processors in combination for each of the target function(s). Unfortunately, the process of connecting these reconfigurable resources in a reconfigurable manner often requires dedication of substantial portions of the available space and metal layers to wiring resources. As a result, the large scale use of associated wiring resources for connectivity is problematic for FPGA devices especially as the metal layers are already very crowded, further increasing both size and complexity of corresponding FPGA designs